Stopping and starting an instance

This page describes how to stop and start a VM instance. For a table that compares the differences between stopping, resetting, and deleting an instance, see Instance life cycle.

You can stop an instance temporarily if you no longer need it and restart it at a later time. A stopped instance retains its persistent disks, its internal IPs, its static external IPs, and its MAC addresses. However, the instance shuts down the guest OS and loses its application state. Essentially, a stopped instance resets to its power-on state and no data is saved. Stop an instance if you want to change the machine type, add or remove attached disks, change the minimum CPU platform, add or remove GPUs, or apply sizing recommendations.

Stopping an instance causes Compute Engine to send the ACPI Power Off signal to the instance. Modern guest operating systems are configured to perform a clean shutdown before powering off in response to the power off signal. Compute Engine waits a short time for the guest to finish shutting down and then transitions the instance to the TERMINATED state.

A stopped instance does not incur charges, but all of the resources that are attached to the instance continue to incur charges. For example, you are charged for persistent disks and external IP addresses according to the price sheet, even if an instance is stopped. To stop being charged for attached resources, you can reconfigure a stopped instance to not use those resources, and then delete the resources.

Before you begin

• If you want to use the command-line examples in this guide:
  1. Install or update to the latest version of the gcloud command-line tool.
  2. Set a default region and zone.
• If you want to use the API examples in this guide, set up API access.

Restrictions

You cannot stop an instance with a local SSD attached. Compute Engine does not prevent you from shutting down an instance from inside the guest operating system if the instance has a local SSD, so take extra precautions.

Local SSDs

You cannot stop an instance that has a local SSD attached. Instead, you must migrate your critical data off of the local SSD to a persistent disk or to another instance before you delete the instance completely. Compute Engine does not prevent you from shutting down the guest operating system on an instance with a local SSD, so take extra precautions if you shut down the guest operating systems on your instances.

Billing

Google does not bill for VM resources after the VMs are in a TERMINATED state.

Specifically, when a VM is RUNNING and is in the process of being stopped (but is not yet TERMINATED), Google bills for vCPUs, memory, GPUs, and local SSD usage. After the STOPPING state ends and a VM enters the TERMINATED state, then Google stops billing for the above-mentioned resources.

Keep in mind that other resources that are attached to a TERMINATED VM continue to incur charges, for example, persistent disks and static external IP addresses.

For more information about instance states, read the Instance life cycle documentation.

Stopping an instance

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.stop on the instance

To stop an instance, use the Google Cloud Console, the gcloud tool, or the API.

Console

1. In the Google Cloud Console, go to the VM instances page.

   Go to the VM instances page

2. Select one or more instances that you want to stop.
3. Click Stop.

gcloud

Use the instances stop command and specify one or more instances that you want to stop.

gcloud compute instances stop example-instance-1 example-instance-2

API

In the API, construct a POST request to stop an instance.

POST https://compute.googleapis.com/compute/v1/projects/myproject/zones/zone/instances/example-instance/stop

A TERMINATED instance still exists with its configuration settings and instance metadata, but it loses its in-memory data and virtual machine state. Any resources that are still attached to the terminated instance remain attached until you manually detach those resources or delete the instance.

After the instance is in the TERMINATED state, you can restart the instance or delete it. You can also leave an instance in a TERMINATED state indefinitely. However, if you do not plan to restart the instance, delete it instead.

Stopping an instance through the OS

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.setMetadata on the instance if using instance-level public SSH keys
• compute.project.setCommonInstanceMetadata on the project if using project-wide SSH keys

Optionally, you can stop an instance through the guest operating system.

Linux

Use the sudo shutdown -h now or sudo poweroff commands. Execute one of these commands while you are logged into the virtual machine:

sudo shutdown -h now

sudo poweroff

Windows

To stop a VM instance based on the Windows OS, on the Start menu, click the arrow next to Log off, and then click Shut down.

Starting a stopped instance

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.start on the instance

To start a stopped instance, use the instances().start method. This boots up a stopped virtual machine instance that is currently in the TERMINATED state.

The start method restarts an instance in a TERMINATED state, whereas methods such as reset() and sudo reboot only work on instances that are currently running. Most instances can be restarted, as long as the instance is in a TERMINATED state, with the exception of instances with local SSDs attached, which cannot be restarted.

Note: You can review the progression of instance statuses that describe the process of starting (or restarting) a new or terminated instance, if you are curious.

Console

1. In the Google Cloud Console, go to the VM Instances page.

   Go to the VM instances page

2. Select the instances that you want to restart.
3. Click the Start button.

gcloud

To reset your instance using gcloud compute:

gcloud compute instances start example-instance

API

In the API, make a POST request to the following URI, replacing the project, zone, and instance name appropriately:

POST https://compute.googleapis.com/compute/v1/projects/myproject/zones/zone/instances/example-instance/start

To restart your instance using the client libraries, construct a request to the instances().start method:

def restartInstance(auth_http, gce_service):
  request = gce_service.instances().start(project="myproject", zone="zone", instance="example-instance")
  response = request.execute(auth_http)

      print response

For more information about this method, see the instances().start reference documentation.

Starting a stopped instance that has encrypted disks

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.startWithEncryptionKey on the instance

If the instance you want to restart uses customer-supplied encryption keys, you must provide those keys when trying to restart the instance.

Console

1. In the Google Cloud Console, go to the VM instances page.

   Go to the VM instances page

2. Click the name of the instance that you want to start. This opens the instance details page.
3. Click Start. A window opens where you can specify encryption keys for the devices that are attached to this instance.
4. Specify encryption keys for each of the encrypted disks that are attached to this instance.
5. Click Start to start the instance.

gcloud

Provide the key using the --csek-key-file flag and the name of the disk when you start the instance. If you are using an RSA-wrapped key, use the gcloud beta component:

gcloud compute instances start instance-name \
  --csek-key-file encryption-key

Replace the following:

• instance-name: The name of the instance.
• encryption-key: The encryption key that you use to encrypt persistent disks that are attached to the instance.

API

In the API, construct a POST request to start the instance using an encryption key. If you are using an RSA-wrapped key, make the request to the Beta API instead of the v1 API.

POST https://compute.googleapis.com/compute/v1/projects/project-id/zones/zone/instances/instance-name/startWithEncryptionKey
{
  "instanceEncryptionKey": {
    "rsaEncryptedKey": "encryption-key"
  },
  "disk": [
    {
       "source": "disk-name",
       "diskEncryptionKey": {
         "rsaEncryptedKey": "encryption-key"
       }
    }
  ]
}

Replace the following:

• project-id: Your project ID.
• zone: The zone for this instance.
• instance-name: The name of the instance.
• encryption-key: The encryption key that you use to encrypt persistent disks that are attached to the instance.
• disk-name The attached disk that is encrypted with a customer-supplied encryption key.

Resetting an instance

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.reset on the instance

Performing a reset on your instance is similar to doing a hard reset on your computer where you might press a reset button or press and hold the power button. Resetting an instance forcibly wipes the memory contents of the machine and resets the virtual machine to its initial state. The instance does not perform a clean shutdown of the guest OS. Throughout this process, the instance remains in RUNNING state.

When you reset an instance, none of the instance properties change. The instance retains properties like its ephemeral IP address, its static external IP address, its persistent disk, and its machine type. However, any data stored in memory is reset. To keep any data stored in memory, you must back up the data.

You can perform a reset on a running instance by using the Reset button in the Cloud Console, the instances reset command in gcloud, or by making a POST request in the API.

Caution: Resetting an instance is a disruptive action; the VM does not do a graceful shutdown of the guest OS and all application state and memory is lost. Make sure you understand the implications of this before resetting your VM.

Console

1. In the Google Cloud Console, go to the VM instances page.

   Go to the VM instances page

2. Check the boxes next to one or more instances that you want to reset.
3. Click the Reset button to reset the instances.

gcloud

To reset your instance using gcloud compute:

gcloud compute instances reset example-instance

API

In the API, make a POST request to the following URI, replacing the project, zone, and instance name appropriately:

POST https://compute.googleapis.com/compute/v1/projects/myproject/zones/zone/instances/example-instance/reset

To reset your instance using the client libraries, construct a request to the instances().reset method:

def resetInstance(auth_http, gce_service):
  request = gce_service.instances().reset(project="myproject", zone="zone", instance="example-instance")
  response = request.execute(auth_http)

  print response

For more information about this method, see the instances().reset reference documentation.

After running the reset command, the subsequent zone operation returns as DONE after the instance has completely shut down and started to reboot.

Using other restart methods

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.instances.setMetadata on the instance if you intend to connect to the instance
• compute.instances.delete on the instance
• compute.instances.insert on the project

Alternatively, you can reset your instance using the following commands:

• sudo reboot (Linux only): Called from within the instance. Wipes the memory and re-initializes the instance with the original metadata, image, and persistent disks. sudo reboot does not pick up any updated versions of the image, and the instance retains the same ephemeral IP address. This is similar to restarting your computer.
• gcloud compute instances delete followed by gcloud compute instances create: This is a completely destructive restart that initializes the instance with any information passed into gcloud compute instances create. You can then select any new images or other resources you'd like to use. The restarted instance will probably have a different IP address. This method potentially swaps the physical machine hosting the instance.

What's next

• Use the interactive serial console to troubleshoot your instance.
• Learn how to change the machine type.